Implement tag name selector for FindElement and related WebDriver commands
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Fix Python and gstreamer instructions for Windows
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Improved the README.md to address missing information for bootstrapping a Windows build.
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Add a HOST_FILE env variable and fix the wdspec setup errors that it causes
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ISSUE-21257: set redirectEnd on PerformanceResourceTiming
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Added the appropriate attribute and setters. Included a Timer struct with a `Drop` function to set this value to zero in error cases. Set the value to `responseEnd` on success. Eliminated tests that now pass.
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Added framebuffer and related attributes to XRWebGLLayer
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Implement the `framebuffer` attribute of `XRWebGLLayer`.
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Add source module to UWP logging output
Updated support/hololens/Servo.cpp to use url: google.com
New debug output:
```
RUST: DEBUG - html5ever::tokenizer - got characters None
RUST: DEBUG - script::script_thread - Processing event FromConstellation(ConstellationControlMsg::NavigationResponse).
RUST: DEBUG - html5ever::tokenizer - processing in state RawData(ScriptData)
```
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